This invention generally relates to the field of mobile equipment for digging ditches, trenches, or the like.
As stated by Newman in his U.S. Pat. No. 4,691,455, which issued to Newman on Sep. 8, 1987 for Trenching Equipment With Hinged Side Plates, in construction and landscaping work it is frequently necessary to dig trenches with walls at angles which vary from the vertical, and many times it is desirable to form a trench wherein each of the side walls thereof are at different angles from the vertical. While there are many prior art devices to form trenches with angled side walls, many are inconvenient to use and, none provide any capability of varying the angle to suit the particular needs of a situation.
Newman thus provided a bucket for a trenching device which can form trenches with walls of varying slope. In particular, Newman discloses a trenching bucket having side plates which are adjustable so that trenches may be formed with walls at various slopes. In FIG. 9 of the Newman patent, the v-shaped trenching bucket is modified to have a floor, plate wherein the side plates are mounted by hinges along the outer edges of the floor plate. Two fan-shaped outer sections are fixed to or formed integral with the ends of the side plates and overlap a stationary, also fan-shaped section which is secured to a support frame. The two fan-shaped outer sections move with the side plates when the orientation of the side plates is adjusted by a corresponding pair of jacks. Newman indicates that the trenches formed by the bucket need not be symmetrical, rather, the side plates may be individually adjusted to provide the desired orientation for each wall of the trench being formed.
What is neither taught nor suggested by Newman is the use of a bucket having adjustable side walls which completely fold outwardly of the center section of the bucket so as to convert the bucket from a bucket which may be merely adjusted to adjust the angles of the walls of the ditches, trenches or the like being excavated, into a larger capacity wide-mouthed bucket, for example, one in which the lower floor of the wide-mouthed bucket is horizontal or almost horizontal across its entire width when placed on level ground, and is therefore well adapted for use in scooping large volumes of loose material.